While not limited thereto, the present invention is particularly adapted for use with overhead trolley rails used in mines and the like to support a suspended conveyor system. In a mine, clearance and headroom are limited, lighting is dim, the mine roof structure may be flawed or uneven, the equipment being handled is generally heavy and cumbersome and, in general, working conditions are quite adverse. In the past, such overhead trolley rails for mine applications typically have been formed from weldments comprising lateral plates welded to the top flange of an I-beam, each lateral plate having two holes drilled therein to receive roof bolts. This construction requires each length of rail to be jacked against the mine roof and held in place while the roof is drilled and the bolts inserted through the holes in the lateral plates and into the drilled holes in the roof. As those skilled in the art will appreciate, a system of this sort is expensive in construction and difficult to install. Furthermore, to retrieve a rail and replace it, the bolts must be pulled or, in the case of resin bolts, cut off. Other prior art trolley rail support systems for mines and other applications are shown, for example, in U.S. Pat. Nos. 1,033,395; 1,577,394; 1,592,814; 1,846,178; 3,219,199; 4,166,134 and U.S. Pat. No. Re. 17,629. U.S. Pat. No. 1,033,359 discloses a rail system which employs two independent hangers for the rail, each of which is secured to an overhead support by a separate bolt. U.S. Pat. No. 1,577,394 shows a system wherein a single bolt secures a bracket to an overhead support, but the bracket must be secured to an I-beam rail by two bolts which extend through two holes which must be drilled in a flange of the I-beam. U.S. Pat. No. 1,592,814 discloses a relatively complex suspension system employing a split trolley rail. U.S. Pat. No. 1,846,178 is directed to a suspension system which requires four separate bolts to secure a rail to a hanger. Each of these bolts must be tightened separately to install the rail. U.S. Pat. No. 3,219,199 discloses a trolley hanger for mine installations which does employ a single roof bolt for each hanger, but wherein brackets carried at the bottoms of each bolt must be slipped over an end of an I-beam flange. That is, the brackets are integral one-piece elements which cannot be separated from the rail without slipping them over an end of that rail. Finally, U.S. Pat. No. 4,166,134 employs two bolts secured to an overhead support in combination with a complex system for securing the rail to a bracket. Some of the foregoing systems are unsuitable for mine environments; and those which are intended for use in mines are cumbersome and not altogether satisfactory.